runtime/objc-private.h

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /*
  26  *      objc-private.h
  27  *      Copyright 1988-1996, NeXT Software, Inc.
  28  */
  29
  30 #if !defined(_OBJC_PRIVATE_H_)
  31     #define _OBJC_PRIVATE_H_
  32
  33     #import <objc/objc-api.h>   // for OBJC_EXPORT
  34
  35     OBJC_EXPORT void checkUniqueness();
  36
  37     #import "objc-config.h"
  38
  39     #import <pthread.h>
  40     #define     mutex_alloc()   (pthread_mutex_t*)calloc(1, sizeof(pthread_mutex_t))
  41     #define     mutex_init(m)   pthread_mutex_init(m, NULL)
  42     #define     mutex_lock(m)   pthread_mutex_lock(m)
  43     #define     mutex_try_lock(m) (! pthread_mutex_trylock(m))
  44     #define     mutex_unlock(m) pthread_mutex_unlock(m)
  45     #define     mutex_clear(m)
  46     #define     mutex_t         pthread_mutex_t*
  47     #define mutex               MUTEX_DEFINE_ERROR
  48     #import <sys/time.h>
  49
  50     #import <stdlib.h>
  51     #import <stdarg.h>
  52     #import <stdio.h>
  53     #import <string.h>
  54     #import <ctype.h>
  55
  56     #import <objc/objc-runtime.h>
  57
  58 #ifdef MACOSX_PANTHER
  59     #import <malloc/malloc.h>
  60 #else
  61     // pre-Panther
  62     #import <objc/malloc.h>
  63 #endif
  64
  65
  66 /* Opaque cookie used in _getObjc... routines.  File format independant.
  67  * This is used in place of the mach_header.  In fact, when compiling
  68  * for NEXTSTEP, this is really a (struct mach_header *).
  69  *
  70  * had been: typedef void *objc_header;
  71  */
  72 #import <mach-o/loader.h>
  73 typedef struct mach_header headerType;
  74
  75 #import <objc/Protocol.h>
  76
  77 typedef struct _ProtocolTemplate { @defs(Protocol) } ProtocolTemplate;
  78 typedef struct _NXConstantStringTemplate {
  79     Class isa;
  80     void *characters;
  81     unsigned int _length;
  82 } NXConstantStringTemplate;
  83
  84 #define OBJC_CONSTANT_STRING_PTR NXConstantStringTemplate*
  85 #define OBJC_CONSTANT_STRING_DEREF &
  86 #define OBJC_PROTOCOL_PTR ProtocolTemplate*
  87 #define OBJC_PROTOCOL_DEREF .
  88
  89 typedef struct {
  90     uint32_t version; // currently 0
  91     uint32_t flags;
  92 } objc_image_info;
  93
  94 // masks for objc_image_info.flags
  95 #define OBJC_IMAGE_IS_REPLACEMENT (1<<0)
  96 #define _objcHeaderIsReplacement(h)  ((h)->info  &&  ((h)->info->flags & OBJC_IMAGE_IS_REPLACEMENT))
  97
  98 /* OBJC_IMAGE_IS_REPLACEMENT:
  99    Don't load any classes
 100    Don't load any categories
 101    Do fix up selector refs (@selector points to them)
 102    Do fix up class refs (@class and objc_msgSend points to them)
 103    Do fix up protocols (@protocol points to them)
 104    Future: do load new classes?
 105    Future: do load new categories?
 106    Future: do insert new methods on existing classes?
 107    Future: do insert new methods on existing categories?
 108 */
 109
 110
 111 // both
 112 OBJC_EXPORT headerType **       _getObjcHeaders();
 113 OBJC_EXPORT Module              _getObjcModules(headerType *head, int *nmodules);
 114 OBJC_EXPORT Class *             _getObjcClassRefs(headerType *head, int *nclasses);
 115 OBJC_EXPORT void *              _getObjcHeaderData(const headerType *head, unsigned *size);
 116 OBJC_EXPORT const char *        _getObjcHeaderName(headerType *head);
 117 OBJC_EXPORT objc_image_info *   _getObjcImageInfo(headerType *head);
 118
 119 // internal routines for delaying binding
 120 void _objc_resolve_categories_for_class (struct objc_class * cls);
 121 void _objc_bindClassIfNeeded(struct objc_class *cls);
 122 void _objc_bindModuleContainingClass(struct objc_class * cls);
 123
 124 // someday a logging facility
 125 // ObjC is assigned the range 0xb000 - 0xbfff for first parameter
 126 #define trace(a, b, c, d) do {} while (0)
 127
 128
 129
 130 OBJC_EXPORT ProtocolTemplate * _getObjcProtocols(headerType *head, int *nprotos);
 131 OBJC_EXPORT NXConstantStringTemplate *_getObjcStringObjects(headerType *head, int *nstrs);
 132 OBJC_EXPORT SEL *               _getObjcMessageRefs(headerType *head, int *nmess);
 133
 134 #define END_OF_METHODS_LIST ((struct objc_method_list*)-1)
 135
 136     typedef struct _header_info
 137     {
 138       const headerType *        mhdr;
 139       Module                    mod_ptr; // NOT adjusted by image_slide
 140       unsigned int              mod_count;
 141       unsigned long             image_slide;
 142       void *                    objcData;     // getObjcHeaderData result
 143       unsigned                  objcDataSize; // getObjcHeaderData result
 144       objc_image_info *         info;    // IS adjusted by image_slide
 145       struct _header_info *     next;
 146     } header_info;
 147     OBJC_EXPORT header_info *_objc_headerStart ();
 148
 149     OBJC_EXPORT int _objcModuleCount();
 150     OBJC_EXPORT const char *_objcModuleNameAtIndex(int i);
 151     OBJC_EXPORT Class objc_getOrigClass (const char *name);
 152
 153     extern struct objc_method_list **get_base_method_list(Class cls);
 154
 155
 156     OBJC_EXPORT const char *__S(_nameForHeader) (const headerType*);
 157
 158     /* initialize */
 159     OBJC_EXPORT void _sel_resolve_conflicts(headerType * header, unsigned long slide);
 160     OBJC_EXPORT void _class_install_relationships(Class, long);
 161     OBJC_EXPORT void *_objc_create_zone(void);
 162
 163     OBJC_EXPORT SEL sel_registerNameNoCopyNoLock(const char *str);
 164     OBJC_EXPORT void sel_lock(void);
 165     OBJC_EXPORT void sel_unlock(void);
 166
 167     /* selector fixup in method lists */
 168
 169     #define _OBJC_FIXED_UP ((void *)1771)
 170
 171     static inline struct objc_method_list *_objc_inlined_fixup_selectors_in_method_list(struct objc_method_list *mlist)
 172     {
 173         unsigned i, size;
 174         Method method;
 175         struct objc_method_list *old_mlist;
 176
 177         if ( ! mlist ) return (struct objc_method_list *)0;
 178         if ( mlist->obsolete != _OBJC_FIXED_UP ) {
 179             old_mlist = mlist;
 180             size = sizeof(struct objc_method_list) - sizeof(struct objc_method) + old_mlist->method_count * sizeof(struct objc_method);
 181             mlist = malloc_zone_malloc(_objc_create_zone(), size);
 182             memmove(mlist, old_mlist, size);
 183             sel_lock();
 184             for ( i = 0; i < mlist->method_count; i += 1 ) {
 185                 method = &mlist->method_list[i];
 186                 method->method_name =
 187                     sel_registerNameNoCopyNoLock((const char *)method->method_name);
 188             }
 189             sel_unlock();
 190             mlist->obsolete = _OBJC_FIXED_UP;
 191         }
 192         return mlist;
 193     }
 194
 195     /* method lookup */
 196     /* --  inline version of class_nextMethodList(Class, void **)  -- */
 197
 198     static inline struct objc_method_list *_class_inlinedNextMethodList(Class cls, void **it)
 199     {
 200         struct objc_method_list ***iterator;
 201
 202         iterator = (struct objc_method_list***)it;
 203         if (*iterator == NULL) {
 204             *iterator = &((((struct objc_class *) cls)->methodLists)[0]);
 205         }
 206         else (*iterator) += 1;
 207         // Check for list end
 208         if ((**iterator == NULL) || (**iterator == END_OF_METHODS_LIST)) {
 209             *it = nil;
 210             return NULL;
 211         }
 212
 213         **iterator = _objc_inlined_fixup_selectors_in_method_list(**iterator);
 214
 215         // Return method list pointer
 216         return **iterator;
 217     }
 218
 219     OBJC_EXPORT BOOL class_respondsToMethod(Class, SEL);
 220     OBJC_EXPORT IMP class_lookupMethod(Class, SEL);
 221     OBJC_EXPORT IMP class_lookupMethodInMethodList(struct objc_method_list *mlist, SEL sel);
 222     OBJC_EXPORT IMP class_lookupNamedMethodInMethodList(struct objc_method_list *mlist, const char *meth_name);
 223     OBJC_EXPORT void _objc_insertMethods( struct objc_method_list *mlist, struct objc_method_list ***list );
 224     OBJC_EXPORT void _objc_removeMethods( struct objc_method_list *mlist, struct objc_method_list ***list );
 225
 226     OBJC_EXPORT IMP _cache_getImp(Class cls, SEL sel);
 227     OBJC_EXPORT Method _cache_getMethod(Class cls, SEL sel, IMP objc_msgForward_imp);
 228
 229     /* message dispatcher */
 230     OBJC_EXPORT IMP _class_lookupMethodAndLoadCache(Class, SEL);
 231     OBJC_EXPORT id _objc_msgForward (id self, SEL sel, ...);
 232
 233     /* errors */
 234     OBJC_EXPORT volatile void _objc_fatal(const char *fmt, ...);
 235     OBJC_EXPORT volatile void _objc_error(id, const char *, va_list);
 236     OBJC_EXPORT volatile void __objc_error(id, const char *, ...);
 237     OBJC_EXPORT void _objc_inform(const char *fmt, ...);
 238     OBJC_EXPORT void _objc_syslog(const char *fmt, ...);
 239
 240     /* magic */
 241     OBJC_EXPORT Class _objc_getFreedObjectClass (void);
 242     OBJC_EXPORT const struct objc_cache emptyCache;
 243     OBJC_EXPORT void _objc_flush_caches (Class cls);
 244
 245     /* locking */
 246     #define MUTEX_TYPE pthread_mutex_t*
 247     #define OBJC_DECLARE_LOCK(MTX) pthread_mutex_t MTX = PTHREAD_MUTEX_INITIALIZER
 248     OBJC_EXPORT pthread_mutex_t classLock;
 249
 250     /* nil handler object */
 251     OBJC_EXPORT id _objc_nilReceiver;
 252     OBJC_EXPORT id _objc_setNilReceiver(id newNilReceiver);
 253     OBJC_EXPORT id _objc_getNilReceiver(void);
 254
 255
 256     typedef struct {
 257        long addressOffset;
 258        long selectorOffset;
 259     } FixupEntry;
 260
 261     static inline int selEqual( SEL s1, SEL s2 ) {
 262        return (s1 == s2);
 263     }
 264
 265     #define OBJC_LOCK(MUTEX)    mutex_lock (MUTEX)
 266     #define OBJC_UNLOCK(MUTEX)  mutex_unlock (MUTEX)
 267     #define OBJC_TRYLOCK(MUTEX) mutex_try_lock (MUTEX)
 268
 269 #if !defined(SEG_OBJC)
 270 #define SEG_OBJC        "__OBJC"        /* objective-C runtime segment */
 271 #endif
 272
 273
 274
 275
 276 static __inline__ int _objc_strcmp(const unsigned char *s1, const unsigned char *s2) {
 277     unsigned char c1, c2;
 278     for ( ; (c1 = *s1) == (c2 = *s2); s1++, s2++)
 279         if (c1 == '\0')
 280             return 0;
 281     return (c1 - c2);
 282 }
 283
 284 static __inline__ unsigned int _objc_strhash(const unsigned char *s) {
 285     unsigned int hash = 0;
 286     for (;;) {
 287         int a = *s++;
 288         if (0 == a) break;
 289         hash += (hash << 8) + a;
 290     }
 291     return hash;
 292 }
 293
 294
 295 // objc per-thread storage
 296 OBJC_EXPORT pthread_key_t _objc_pthread_key;
 297 typedef struct {
 298     struct _objc_initializing_classes *initializingClasses; // for +initialize
 299
 300     // If you add new fields here, don't forget to update
 301     // _objc_pthread_destroyspecific()
 302
 303 } _objc_pthread_data;
 304
 305
 306 // Class state
 307 #define ISCLASS(cls)            ((((struct objc_class *) cls)->info & CLS_CLASS) != 0)
 308 #define ISMETA(cls)             ((((struct objc_class *) cls)->info & CLS_META) != 0)
 309 #define GETMETA(cls)            (ISMETA(cls) ? ((struct objc_class *) cls) : ((struct objc_class *) cls)->isa)
 310 #define ISINITIALIZED(cls)      ((((volatile long)GETMETA(cls)->info) & CLS_INITIALIZED) != 0)
 311 #define ISINITIALIZING(cls)     ((((volatile long)GETMETA(cls)->info) & CLS_INITIALIZING) != 0)
 312
 313
 314 #endif /* _OBJC_PRIVATE_H_ */
 315